Polyarylether copolymers based on diol sugar alcohols

Abstract

The present invention relates to a process for the preparation of polyarylether copolymers (P), to the polyarylether copolymers (P) obtained by said process, and to a process for the preparation of membranes comprising the polyarylether copolymers (P), and to the membranes themselves.

Description

[Technical field]

[0001] The present invention relates to a process for the preparation of polyarylether copolymers (P), to the polyarylether copolymers (P) obtainable by said process, and to a process for the preparation of membranes comprising the polyarylether copolymers (P), and to the membranes themselves. [Background technology]

[0002] Polyarylether polymers include polyarylethersulfone polymers and polyaryletherketone polymers.Polyaryletherpolymers belong to the group of high-performance thermoplastics and are characterized by high heat distortion resistance, good mechanical properties, and inherent flame retardancy (EM Koch, H.-M. Walter Kunststoffe 80(1990)1146; E. Doering, Kunststoffe 80(1990)1146; N. Inchaurohdo-Nehm, Kunsstoffe 98(2008)190).

[0003] The preparation of polyarylethers can be carried out either by the so-called hydroxide process or by the so-called carbonate process. In the preparation of polyaryletherpolymers by the hydroxide process, the corresponding diphenolates are prepared from aromatic dihydroxy compounds in a first step. For this purpose, the aromatic dihydroxy compounds are deprotonated with a strong base, for example sodium hydroxide. The deprotonation is carried out in an aprotic polar solvent, for example dimethylsulfoxide (DMSO). Water is released by deprotonation of the aromatic dihydroxy compounds. For the hydroxide process, it is necessary to remove the water formed as completely as possible from the diphenolates. The anhydrous diphenolates formed are subsequently reacted with aromatic dihalogen compounds in a second step. In the second step, the polyaryletherpolymers are formed. For the deprotonation of the aromatic dihydroxy compounds in the first step of the preparation of polyaryletherpolymers by the hydroxide process, the stoichiometric ratio of the aromatic dihydroxy compounds to the sodium hydroxide used for the deprotonation must be maintained as accurately as possible. Even small deviations in the stoichiometric ratio can result in a dramatic decrease in the molecular weight of the polymer formed in the reaction.

[0004] The strong base used in the hydroxide method can also cleave the ether bond formed in the polycondensation, which leads to a further decrease in the molecular weight of the polymer formed in the reaction. Therefore, the preparation of polyarylether polymers by the hydroxide method is prone to error and is very complicated and expensive due to the complexity of the measurements to maintain the exact stoichiometric ratio and the two-step synthesis.

[0005] For the carbonate process, aromatic dihydroxy compounds and aromatic dihalogen compounds are reacted together in the presence of a carbonate, preferably potassium carbonate, where typically N,N-dimethylacetamide, DMF, N-ethylpyrrolidone or NMP is used as the solvent and toluene or chlorobenzene is added as an azeotropic agent to remove water.

[0006] In the carbonate process, prior to the actual polycondensation reaction, the azeotrope of toluene and water is distilled off from the reaction mixture in which the diphenolate dianion is formed from the aromatic dihydroxy compound. The carbonate process has the advantage over the hydroxide process that the excess of potassium carbonate can be varied in a relatively wide range without decreasing the molecular weight of the polymer formed. This simplifies the control of the reaction compared to the hydroxide process.

[0007] Overviews of the preparation of polyarylethersulfone polymers by the hydroxide method and the carbonate method are given, for example, in JE McGrath et al., POLYMER 25, 1984, pp. 1827-1836. Furthermore, the preparation of polyarylethersulfone polymers is described in the following patent applications, US Pat. No. 4,870,153 (US4870153), EP113112 (EP113112), EP297363 (EP297363) and EP135130 (EP135130), which are incorporated herein by reference. In these patent applications, suitable starting materials, catalysts, solvents and ratios of the components used, as well as reaction times and reaction temperatures can be found.

[0008] Polyarylether polymers are also used as materials for manufacturing membranes and filter systems for water purification by microfiltration or ultrafiltration. In the prior art, bio-based diols, such as sugar alcohols, have been incorporated into polyarylether polymers to improve their suitability in membrane applications.

[0009] Several scientific publications have disclosed the preparation and properties of polyarylethersulfones and polyaryleneetherketones derived from biobased diols (Kricheldorf et al. J Polym. Sci. Part A: Polymer Chemistry, Vol 33, 2667-2671(1995); Chatti et al. High Performance Polymers, 21: 105-118, 2009; Abderrazak et al. Macromol. Chem. Phys. 2013, 214, 1423-1433; Belgacem et al. Designed Monomers and Polymers, 2016, Vol 19, No.3, 248-255). Polyarylene ether sulfones derived from 1,4:3,6-dianhydrohexitols have also been disclosed in WO 2014 / 072473 and WO 2016 / 032179.

[0010] Sugar alcohols such as isosorbide, isomannide and isoidide are produced by hydrogenating glucose to give sorbitol. Isosorbide is obtained by acid-catalyzed dehydration of D-sorbitol, which gives the monocyclic furanoid sorbitan, which upon further dehydration forms the bicyclic furofuran derivative isosorbide.

[0011] [ka]

[0012] Isosorbide, isomannide and isoidide are technical monomers produced on an industrial scale.

[0013] The use of isosorbide-containing polyarylether polymers for membranes is known from the literature (EP 3430076, EP 3850032).

[0014] To improve the hydrophilicity of polyarylether polymers, especially for membrane applications, the incorporation of aliphatic polyether blocks, such as polyethylene oxide, is usually used (Hancock, Macromolecules 1996, 29, 7619, and EP 2739668). EP 3850031 describes the preparation and use of polyarylether polymers containing isosorbide and polyalkylene oxide. The copolymers have relatively low molecular weights and can only be used as hydrophilic additives in membrane formulations. [Prior art documents] [Patent documents]

[0015] [Patent Document 1] European Patent No. 113112 [Patent Document 2] European Patent Application Publication No. 297363 [Patent Document 3] European Patent Application Publication No. 135130 [Patent Document 4] International Publication No. 2014 / 072473 [Patent Document 5] International Publication No. 2016 / 032179 [Patent Document 6] European Patent No. 3430076 [Patent Document 7] European Patent No. 3850032 [Patent Document 8] European Patent No. 2739668 [Patent Document 9] European Patent No. 3850031 [Non-patent literature]

[0016] [Non-Patent Document 1] E.M.Koch, H.-M.Walter Kunststoffe 80(1990)1146 [Non-Patent Document 2] E.Doering, Kunststoffe 80(1990)1146 [Non-Patent Document 3] N.Inchaurohdo-Nehm, Kunsstoffe 98(2008)190 [Non-Patent Document 4] J.E.McGrath et al., POLYMER 25, 1984, pages 1827 - 1836 [Non-Patent Document 5] Kricheldorf et al. J Polym. Sci. Part A: Polymer Chemistry, Vol 33, 2667 - 2671(1995) [Non-Patent Document 6] Chatti et al. High Performance Polymers, 21: 105 - 118, 2009 [Non-Patent Document 7] Abderrazak et al. Macromol. Chem. Phys. 2013, 214, 1423 - 1433 [Non-Patent Document 8] Belgacem et al. Designed Monomers and Polymers, 2016, Vol 19, No.3, 248 - 255 [Non-Patent Document 9] Hancock, Macromolecules 1996, 29, 7619 [Summary of the Invention] [Problems to be Solved by the Invention]

[0017] The object of the present invention is therefore to provide a method for the preparation of polyarylether copolymers (P), which does not have the disadvantages of the methods described in the prior art, or has them to a lesser extent. The method should be simple to carry out, as error-free as possible, and inexpensive. The polyarylether copolymers (P) obtained by the method should have a high molecular weight, improved color, and form homogeneous solutions for the production of membranes. Furthermore, the membranes produced from the polyarylether copolymers (P) should exhibit good water permeability and good molecular weight cut-off, and a low tendency to foul. [Means for solving the problem]

[0018] The above problem is solved according to the invention by a process for the preparation of a polyarylether copolymer (P) comprising, as components: (A1) at least one dihalodiphenyl sulfone component having a 4,4'-dihalodiphenyl sulfone content of at least 99.65% by weight, based on the total weight of the at least one dihalodiphenyl sulfone component in component (A1); (B1) at least one sugar alcohol selected from the group consisting of isosorbide, isomannide and isoidide; (B2) at least one aromatic dihydroxyl component; (B3) optionally at least one dihydroxyl polyalkylene oxide; A reaction mixture (R G ) The reaction mixture (R G ) is the reaction mixture (R G (B1), 35 to 70 mol % of component (B1), 30 to 65 mol % of component (B2), and optionally 0.0 to 5 mol % of component (B3) based on the total amount of components (B1), (B2), and optionally (B3) contained in The problem is solved by the method.

[0019] Surprisingly, the polyarylether copolymers (P) obtained by the process of the present invention can be prepared in short condensation times and the resulting product mixtures (P G It has been found that polyarylether copolymers (P) can be filtered in reduced filtration times and lead to polyarylether copolymers (P) with reduced chloride content. Furthermore, membranes made from polyarylether copolymers (P) exhibit good water permeability, good molecular weight cut-off, and improved tensile properties, especially tensile elongation.

[0020] The reaction mixture (R G ) To prepare the polyarylether copolymers (P) according to the invention, a reaction mixture (R 1 ) containing the components (A1), (B1), (B2) and optionally (B3) is prepared. G ) is reacted as described below. Furthermore, in a preferred embodiment, the reaction mixture (R G ) comprises at least one aprotic polar solvent as component (C) and at least one carbonate component as component (D).

[0021] Another subject of the present invention is therefore a reaction mixture (R G ) is further (C) at least one aprotic polar solvent, and (D) at least one carbonate component The method includes:

[0022] Components (A1), (B1), (B2), and optionally (B3) enter into a polycondensation reaction.

[0023] Component (D), when present, acts as a base to deprotonate components (B1), (B2), and optionally (B3) during the condensation reaction, and component (C), when present, acts as a solvent.

[0024] The reaction mixture (R G) is understood to mean the mixture used to prepare the polyarylether copolymer (P) in the process according to the invention. In this case, the reaction mixture (R G All details given for the reaction mixture (R ) relate to the mixture present before polycondensation. Polycondensation takes place during the process according to the invention, in which the reaction mixture (R G ) reacts by polycondensation of components (A1), (B1), (B2), and optionally (B3) to obtain the target product polyarylether copolymer (P). The mixture obtained after polycondensation and containing the polyarylether copolymer (P) target product is referred to as product mixture (P G ) is also called.

[0025] The reaction mixture (R G The components of the 1st step are generally reacted simultaneously. The individual components can be mixed in an upstream step and reacted subsequently. It is also possible to feed the individual components to a reactor where they are mixed and then reacted.

[0026] In the process according to the invention, the reaction mixture (R G The individual components of (B1), (B2) and optionally (B3) are generally reacted simultaneously. The reaction is preferably carried out in one step. This means that the deprotonation of components (B1), (B2) and optionally (B3) and also the condensation reaction between components (A1), (B1), (B2) and optionally (B3) are preferably carried out in a single step without isolation of intermediate products, such as the deprotonated species of components (B1), (B2) and optionally (B3).

[0027] The process according to the invention is preferably carried out by the so-called carbonate method. The process according to the invention is preferably not carried out by the so-called hydroxide method. This means that the process according to the invention is preferably not carried out in two stages with isolation of the phenolate anion.

[0028] Ingredient (A1) The reaction mixture (R G) comprises at least one dihalodiphenylsulfone component as component (A1). In this case, the term "at least one dihalodiphenylsulfone component" is understood to mean exactly one dihalodiphenylsulfone component and also mixtures of two or more dihalodiphenylsulfone components.

[0029] The reaction mixture (R G The at least one dihalodiphenyl sulfone component contained in component (A1) has a 4,4'-dihalodiphenyl sulfone content of at least 99.65% by weight, based on the total weight of the at least one dihalodiphenyl sulfone component in component (A1), more preferably based on the total weight of component (A1).

[0030] In a preferred embodiment, the at least one dihalodiphenyl sulfone component has a 4,4'-dihalodiphenyl sulfone content of at least 99.7% by weight, more preferably at least 99.75% by weight, and more preferably at least 99.80% by weight, each based on the total weight of the at least one dihalodiphenyl sulfone component in component (A1).

[0031] Component (A1) is preferably used as a monomer. This is because the reaction mixture (R G ) comprises component (A1) as a monomer and not as a prepolymer.

[0032] In a preferred embodiment, the at least one dihalodiphenyl sulfone component (component (A1)) is selected from the group consisting of dichlorodiphenyl sulfone, difluorodiphenyl sulfone, and dibromodiphenyl sulfone, with a content of 4,4'-dichlorodiphenyl sulfone, 4,4'-dibromodiphenyl sulfone, and 4,4'-difluorodiphenyl sulfone of at least 99.65% by weight, respectively, based on the total weight of dichlorodiphenyl sulfone, difluorodiphenyl sulfone, and dibromodiphenyl sulfone in the components in component (A1).

[0033] Another subject of the present invention is therefore a reaction mixture (R G ) is further (C) at least one aprotic polar solvent, and (D) at least one carbonate component The object of the present invention is to provide a method comprising the steps of:

[0034] The most preferred component (A1) is dichlorodiphenyl sulfone having a content of 4,4'-dichlorodiphenyl sulfone of at least 99.65% by weight, based on the total weight of dichlorodiphenyl sulfone in component (A).

[0035] Preferably the content of 4,4'-dihalodiphenylsulfone in the dihalodiphenylsulfone in component (A1) is determined by GC, details of the applied method are given in the experimental section.

[0036] In a further particularly preferred embodiment, component (A1) consists of dichlorodiphenyl sulfone having a content of 4,4'-dichlorodiphenyl sulfone of more than 99.65% by weight, based on the total weight of dichlorodiphenyl sulfones in component (A1), where the content is determined by GC.

[0037] In a preferred embodiment, component (A1) is (a) at least 99.65% by weight, preferably at least 99.7% by weight, more preferably at least 99.75% by weight, and particularly preferably at least 99.80% by weight, of 4,4′-dihalodiphenylsulfone; (b) 0 to 0.35% by mass, preferably 0 to 0.3% by mass, more preferably 0 to 0.25% by mass, and particularly preferably 0 to 0.2% by mass of impurities, and (c) 0 to 0.35% by mass, preferably 0 to 3.0% by mass, more preferably 0 to 0.25% by mass, and particularly preferably 0 to 0.2% by mass of at least one solvent It consists of:

[0038] In a preferred embodiment, the total amount of components (a), (b) and (c) contained in component (A1) is 100 mass %. When component (A1) does not contain impurities (b) and solvent (c), component (A1) consists of 100% 4,4'-dihalodiphenylsulfone.

[0039] In a preferred embodiment, impurity (b) comprises one or more compounds selected from the group consisting of 2,4'-dichlorodiphenyl sulfone, 3,4'-dichlorodiphenyl sulfone, 4,4'-dichlorodiphenyl sulfoxide, 2,4'-dichlorodiphenyl sulfoxide and one or more carboxylic acid compounds, each of which is at least 90% by mass, preferably at least 95% by mass, more preferably at least 98% by mass, and particularly preferably at least 99% by mass, based on the total mass of impurities (b) contained in component (A1).

[0040] The carboxylic acid compound optionally contained as impurity (b) in component (A1) may be only one carboxylic acid or a mixture of at least two different carboxylic acids. Preferably, the carboxylic acid is at least one aliphatic carboxylic acid.

[0041] The total content of the isomers 2,4'-dichlorodiphenylsulfone and 3,4'-dichlorodiphenylsulfone in component (A1) is preferably in the range of 0 to 3500 ppm by mass, more preferably in the range of 0 to 2500 ppm by mass, and most preferably in the range of 0 to 2000 ppm by mass, based on the total mass of component (A1). The contents of the above-mentioned isomers are specified as described in the Examples section below.

[0042] The total content of 4,4'-dichlorodiphenyl sulfoxide and 2,4'-dichlorodiphenyl sulfoxide in component (A1) is preferably in the range of 0 to 3500 ppm by mass, more preferably in the range of 0 to 2500 ppm by mass, and most preferably in the range of 0 to 2000 ppm by mass, relative to the total mass of component (A1).

[0043] Component (A1) optionally comprises at least one solvent (c). In the context of the present invention, the term "at least one solvent (a)" means exactly one solvent (c) as well as mixtures of two or more solvents (c).

[0044] The at least one solvent (c) may be, for example, water, symmetrical or asymmetrical, branched or linear ethers, such as diethyl ether or methyl tert-butyl ether, substituted or unsubstituted aromatic solvents, such as toluene, monochlorobenzene or benzene, low molecular carboxylic acids, in particular C 1 ~C 3 -Carboxylic acids or low molecular weight alcohols, especially C 1 ~C 3 Preferably, the organic solvent is methanol, ethanol, isopropanol, acetone, methyl tert-butyl ether, acetic acid, toluene, ethyl acetate, or monochlorobenzene. Particularly preferably, the organic solvent is C 1 ~C 3 an alcohol, in particular methanol, ethanol or isopropanol. Most preferably, said organic solvent is methanol.

[0045] Ingredients (B1) The reaction mixture (R G ) comprises as component (B1) at least one sugar alcohol selected from the group consisting of isosorbide, isomannide and isoidide. In this case, the term "at least one sugar alcohol selected from the group consisting of isosorbide, isomannide and isoidide" is understood to mean exactly one sugar alcohol and also mixtures of two or more sugar alcohols selected from the group consisting of isosorbide, isomannide and isoidide.

[0046] The reaction mixture (R G The component (B1) contained in the above-mentioned product is at least one sugar alcohol selected from the group consisting of isosorbide, isomannide, and isoidide.

[0047] Component (B1) is known to those skilled in the art. Isosorbide, isomannide and isoidide belong to the family of 1,4:3,6-dianhydrohexitols and are of formula I: [ka]

[0048] As already discussed above, the isosorbide, isomannide and isoidide used in the prior art are technical monomers having a purity of more than 98% by weight, preferably more than 98.5% by weight.

[0049] The reaction mixture (R G ) is preferably a reaction mixture (R G The component (B3) is contained in an amount of 0.0 to 5 mol %, more preferably 0.0 to 4 mol %, particularly preferably 0.0 to 3 mol %, and most preferably 0.0 to 2 mol %, based on the total amount of the components (B1), (B2), and optionally (B3) contained in the copolymer.

[0050] In the process according to the invention, isosorbide, isomannide and / or isoidide are each used having a purity of at least 99% by weight.

[0051] The reaction mixture (R G ) is preferably a reaction mixture (R G ) contains 35 to 69 mol % of component (B1), 31 to 65 mol % of component (B2), and 0.0 to 4 mol % of component (B3), based on the total amount of components (B1), (B2), and optionally (B3) contained in the copolymer.

[0052] In a more preferred embodiment, the reaction mixture (R G ) is the reaction mixture (R G ) contains 37 to 67 mol % of component (B1), 33 to 63 mol % of component (B2), and 0.0 to 3 mol % of component (B3), based on the total amount of components (B1), (B2), and optionally (B3) contained in the copolymer.

[0053] In an even more preferred embodiment, the reaction mixture (R G ) is the reaction mixture (R G ) contains 40 to 65 mol % of component (B1), 35 to 60 mol % of component (B2), and 0.0 to 2 mol % of component (B3) relative to the total amount of components (B1), (B2), and optionally (B3) contained in the copolymer.

[0054] Particularly preferred as component (B1) is isosorbide. In other words, in the particularly preferred embodiment in which component (B1) consists of isosorbide, said isosorbide preferably has a purity above the above-mentioned purity and may still contain the above-mentioned impurities.

[0055] Ingredients (B2) The reaction mixture (R G ) comprises at least one aromatic dihydroxyl compound as component (B2). In this case, the term "at least one aromatic dihydroxyl compound" is understood to mean exactly one aromatic dihydroxyl compound and also mixtures of two or more aromatic dihydroxyl compounds. The aromatic dihydroxyl compounds used are typically compounds having two phenolic hydroxyl groups. In a preferred embodiment, the reaction mixture (R G ) contains metal carbonate, so the reaction mixture (R G The hydroxyl groups of component (B2) in may be present at least partially in deprotonated form.

[0056] Component (B2) is preferably used as a monomer. This is because the reaction mixture (R G ) preferably comprises component (B2) as a monomer and not as a prepolymer.

[0057] Suitable aromatic dihydroxyl compounds (component (B2)) are, for example, selected from the group consisting of 4,4'-dihydroxybiphenyl, 4,4'-dihydroxydiphenyl sulfone and bisphenol A (IUPAC name: 4,4'-(propane-2,2-diyl)diphenol).

[0058] In one embodiment of the present invention, the reaction mixture (R G ) does not contain bisphenol A. In another embodiment, the reaction mixture (R G In yet another embodiment, the reaction mixture (R G ) does not include compounds with three or more functionalities, such as 1,1,1-trihydroxyphenylethane.

[0059] Component (B2) is preferably present in the reaction mixture (R G ), based on the total weight of component (B2) in the composition (B1), comprises at least 50% by weight, more preferably at least 80% by weight, particularly preferably at least 90% by weight, and in particular at least 98% by weight, of an aromatic dihydroxyl compound selected from the group consisting of 4,4'-dihydroxybiphenyl, 4,4'-dihydroxydiphenyl sulfone and bisphenol A. 4,4'-dihydroxybiphenyl and 4,4'-dihydroxydiphenyl sulfone are preferred as aromatic dihydroxyl compounds, and 4,4'-dihydroxybiphenyl is particularly preferred as aromatic dihydroxyl compound.

[0060] A further object of the present invention is therefore to provide a method for preparing a dihydroxy component (B2) from a reaction mixture (R G (B2)) contains at least 50% by mass of 4,4'-dihydroxybiphenyl based on the total mass of component (B2) contained in the

[0061] Thus, the present invention relates to a process for the preparation of a reaction mixture (R G The present invention also relates to a process for the preparation of a reaction mixture (R 1 ), comprising at least 50% by weight, based on the total weight of component (B2) in the reaction mixture (R 2 ), of an aromatic dihydroxyl compound selected from the group consisting of 4,4'-dihydroxybiphenyl, 4,4'-dihydroxydiphenyl sulfone and bisphenol A. In a preferred embodiment, component (B2) is G) contains at least 50% by weight, preferably at least 80% by weight, particularly preferably at least 90% by weight and in particular at least 98% by weight of 4,4'-dihydroxybiphenyl, based on the total weight of component (B2) in

[0062] In a particularly preferred embodiment, component (B2) consists essentially of 4,4'-dihydroxybiphenyl. In this case, "consists essentially of" means that component (B2) is a 4,4'-dihydroxybiphenyl, ... G %, preferably more than 99.5% by weight and particularly preferably more than 99.9% by weight of 4,4'-dihydroxybiphenyl, based on the total weight of component (B2) in

[0063] In a particularly preferred embodiment, component (B2) consists of 4,4'-dihydroxybiphenyl.

[0064] Ingredient (B3) The reaction mixture (R G ) optionally comprises at least one dihydroxypolyalkylene oxide as component (B3). In this case, the term "at least one dihydroxypolyalkylene oxide" is understood to mean exactly one dihydroxypolyalkylene oxide, and also mixtures of two or more dihydroxypolyalkylene oxides. When used, dihydroxypolyalkylene oxides are typically compounds having two hydroxyl groups. In a preferred embodiment, the reaction mixture (R G ) contains metal carbonate, so the reaction mixture (R G The hydroxyl groups of component (B3) in may be present at least partially in deprotonated form.

[0065] The reaction mixture (R G ) is the reaction mixture (R G ) contains 0.0 to 5 mol % of component (B3) based on the total amount of components (B1), (B2), and (B3) contained therein.

[0066] Component (B3) can generally be a diol. Component (B3) can generally consist essentially of oxyalkylene units, which may also be called alkylene oxide units in the following. Oxyalkylene units are, as is known in principle, of the general formula -R 1 -O- unit. In this formula, R 1 is a divalent aliphatic hydrocarbon group, which may optionally also bear at least one further substituent. 1 Said at least one substituent on the radical may in particular comprise one or more O-containing groups, for example one or more OH groups.Of course, component (B3) may also comprise two or more different oxyalkylene units.

[0067] The oxyalkylene unit is in particular -(CH 2 ) 2 -O-, -(CH 2 ) 3 -O-, -(CH 2 ) 4 -O-, -CH 2 -CH(R 2 )-O-, -CH 2 -CHOR 3 -CH 2 -O-, where R 2 is an alkyl group, especially C 1 ~C 24 - an alkyl or aryl group, in particular phenyl, R 3 is hydrogen or C 1 ~C 24 -alkyl.

[0068] Component (B3) may also contain further structural units, such as ester groups, carbonate groups or amino groups. They may further contain one or more starter molecules which are used in the initiation of the polymerization of the polyalkylene oxide or fragments thereof. Examples are the terminal groups R 2 -O-, where R 2 is as defined above.

[0069] Component (B3) is an ethylene oxide unit -(CH 2 )2 -O- and / or propylene oxide units -CH 2 -CH(CH 3 )-O- as a main component, while higher alkylene oxide units, i.e. those with more than 3 carbon atoms, are preferably present only in small amounts to fine-tune the properties. Component (B3) may be a random, gradient, alternating or block copolymer comprising ethylene oxide and propylene oxide units. The amount of higher alkylene oxide units generally does not exceed 10% by weight, preferably 5% by weight, relative to the molecular weight (Mn) of component (B3). Component (B3) may preferably comprise at least 50% by weight of ethylene oxide units, relative to the molecular weight (Mn) of component (B3), preferably 75% by weight, and more preferably at least 90% by weight, of ethylene oxide units, relative to the molecular weight (Mn) of component (B3). It may be very particularly preferred that component (B3) is pure polyoxyethylene.

[0070] Component (B3) can be obtained as known in principle or using methods known in principle, for example by polymerizing at least one alkylene oxide and / or cyclic ether having at least 3 carbon atoms and optionally at least one further component. They can further be prepared by polycondensing at least one dialcohol and / or polyalcohol, a suitable starter and optionally at least one further monomer component. Examples of the at least one suitable alkylene oxide include ethylene oxide and propylene oxide, 1-butene oxide, 2,3-butene oxide, 2-methyl-1,2-propene oxide (isobutene oxide), 1-pentene oxide, 2,3-pentene oxide, 2-methyl-1,2-butene oxide, 3-methyl-1,2-butene oxide, 2,3-hexene oxide, 3,4-hexene oxide, 2-methyl-1,2-pentene oxide, 2-ethyl-1,2-butene oxide, 3-methyl-1,2-pentene oxide, decene oxide, 4-methyl-1,2-pentene oxide, styrene oxide, or formed from oxide mixtures of industrially available raffinate streams. An example of the at least one cyclic ether includes tetrahydrofuran. The skilled person will make the appropriate selection among said monomers and further components according to the desired properties of component (B3) and thus of block ii) and of the polyarylene ether copolymer, respectively, in which respect one of the desired properties of component (B3) is typically its hydrophilicity.

[0071] Component (B3) may be branched or star-shaped. This type of component (B3) can be obtained by using at least one starter molecule with at least three arms. Examples of suitable starters include glycerol, trimethylolpropane, pentaerythritol or ethylenediamine.

[0072] Component (B3) may be a polyalkylene oxide having a low number average of alkylene oxide units. Depending on the desired properties, the number average of the alkylene oxide units may be higher. It may be preferred that the polyalkylene oxide has a number average mass of 200 to 20000 g / mol.

[0073] The reaction mixture (R G ) may contain as component (B3') a polyalkylene oxide having only one hydroxy group (-OH), where the second hydroxy group is preferably end-capped with an alkyl group having 1 to 32 carbon atoms. For component (B3'), the remarks and preferences given above for component (B3) apply correspondingly.

[0074] Ingredients (C) The reaction mixture (R G ) in a preferred embodiment comprises at least one aprotic polar solvent as component (C). According to the invention, "at least one aprotic polar solvent" is understood to mean exactly one aprotic polar solvent and also mixtures of two or more aprotic polar solvents.

[0075] Suitable aprotic polar solvents are, for example, anisole, dimethylformamide, dimethylsulfoxide, sulfolane, N,N-dimethylacetamide, N-methyl-2-pyrrolidone, N-ethyl-2-pyrrolidone, and further mixtures of these solvents.

[0076] Another subject of the invention is therefore a process, in which component (C) is at least one solvent selected from the group consisting of anisole, dimethylformamide, dimethylsulfoxide, sulfolane, N,N-dimethylacetamide, N-methyl-2-pyrrolidone and N-ethyl-2-pyrrolidone.

[0077] Preferred aprotic polar solvents are N-methyl-2-pyrrolidone, N-ethyl-2-pyrrolidone and further mixtures of these solvents. N-methyl-2-pyrrolidone is particularly preferred as aprotic polar solvent.

[0078] Thus, the present invention provides a reaction mixture (R G ) comprises N-methyl-2-pyrrolidone as component (C).

[0079] In a preferred embodiment, component (C) is G ), based on the total weight of component (C) in the composition, at least 50% by weight, preferably at least 80% by weight, particularly preferably at least 90% by weight and in particular at least 98% by weight of at least one solvent selected from the group consisting of N-methyl-2-pyrrolidone and N-ethyl-2-pyrrolidone. N-methyl-2-pyrrolidone is particularly preferred as component (C).

[0080] In a further embodiment, component (C) consists essentially of N-methyl-2-pyrrolidone. In this case, "consists essentially of" is understood to mean that component (C) comprises more than 99% by weight, particularly preferably more than 99.5% by weight, particularly preferably more than 99.9% by weight of at least one aprotic polar solvent selected from the group consisting of N-methyl-2-pyrrolidone and N-ethyl-2-pyrrolidone, with N-methyl-2-pyrrolidone being preferred.

[0081] The aprotic polar solvent (component (C)) is an industrial solvent produced on an industrial scale and, as a result, generally contains impurities.

[0082] In a preferred embodiment, component (C) consists of N-methyl-2-pyrrolidone, also called NMP or N-methylpyrrolidone.

[0083] According to the present invention, in a preferred embodiment, the reaction mixture (R G) does not contain substances which form azeotropes with water. The water of reaction is formed in the process according to the invention in the polycondensation reaction between components (A1), (B1), (B2) and optionally (B3). In the processes described in the prior art, it is often necessary to add an azeotroping agent to remove the water of reaction which is formed as an azeotrope in the condensation reaction.

[0084] "Azeotrope" is understood according to the present invention to mean a mixture of water and one or more further substances that cannot be separated by distillation. Thus, "azeotrope" is understood according to the present invention to mean a mixture of water and one or more substances that behaves as if it were a pure substance in the phase transition from liquid to gas. In a preferred embodiment, the reaction mixture (R G ) does not contain toluene or chlorobenzene.

[0085] Ingredients (D) The reaction mixture (R G ) in a preferred embodiment comprises at least one metal carbonate as component (D). According to the invention, "at least one metal carbonate" is understood to mean exactly one metal carbonate and also a mixture of two or more metal carbonates. The metal carbonate is preferably anhydrous. Alkali metal carbonates and / or alkaline earth metal carbonates are preferred as metal carbonates. At least one metal carbonate selected from the group consisting of sodium carbonate, potassium carbonate and calcium carbonate is particularly preferred as metal carbonate. Potassium carbonate is most preferred.

[0086] In a preferred embodiment, component (D) consists essentially of potassium carbonate. In this case, "consists essentially of" means that component (D) is a component that is present in the reaction mixture (R G %, preferably more than 99.5% by weight, particularly preferably more than 99.9% by weight, of potassium carbonate, based on the total weight of component (D) in

[0087] In a particularly preferred embodiment, component (D) consists of potassium carbonate.

[0088] Particularly preferred as potassium carbonate is potassium carbonate having a volume weighted mean particle size of less than 200 μm. The volume weighted mean particle size of potassium carbonate is determined in a suspension of potassium carbonate in N-methyl-2-pyrrolidone using a particle size analyzer.

[0089] In a preferred embodiment, the reaction mixture (R G ) does not include substances that form azeotropes with water.

[0090] In a preferred embodiment, the reaction mixture (R G The sum of the total masses of components (A1), (B1), (B2), optionally (B3), (C) and (D) contained in the reaction mixture (R G ), more preferably at least 90%, even more preferably at least 95%, and particularly preferably at least 98% by weight, based on the total weight of the components (a) and (b).

[0091] Thus, in a further particularly preferred embodiment, the present invention also relates to a process, wherein component (A1) is dichlorodiphenyl sulfone having a content of 4,4'-dichlorodiphenyl sulfone of at least 99.65% by weight, component (B1) is at least one sugar alcohol selected from the group consisting of isosorbide, isomannide and isoidide, where isosorbide, isomannide and isoidide, if used, each have a purity of at least 99% by weight, and component (B2) is 4,4'-dihydroxybiphenyl, and (B3), if present, is polyethylene oxide with a number average molecular weight of 500 to 9000 g / mol.

[0092] The reaction mixture (R G The ratio of components (A1), (B1), (B2) and (B3) in the reaction mixture (R) can vary within wide limits. G ) generally contains 0.1 to 0.7 mol of component (B1), 0.3 to 0.65 mol of component (B2), and 0 to 0.05 mol of component (B3) per 1 mol of component (A1).

[0093] Polyarylether copolymer (P) To prepare the polyarylether copolymer (P) according to the invention, a reaction mixture (R G ) are reacted preferably under the conditions of the so-called carbonate process. The reaction (polycondensation reaction) is generally carried out at a temperature in the range of 80 to 250° C., preferably in the range of 100 to 220° C., the upper limit of which is determined by the boiling point of the solvent at standard pressure (1013.25 mbar). The reaction is generally carried out at standard pressure. The reaction is preferably carried out over a time interval in the range of 0.5 to 12 hours, in particular in the range of 1 to 10 hours.

[0094] After condensation, the salt formed is separated from the resulting polymer suspension by filtration or other separation techniques.

[0095] The isolation of the polyarylether copolymer (P) obtained according to the invention can be carried out, for example, by precipitation of the polymer solution in water or a mixture of water and another solvent. The precipitated polyarylether copolymer (P) can subsequently be extracted with water and then dried. In one embodiment of the invention, the precipitate can also be taken up in an acidic medium. Suitable acids are, for example, organic or inorganic acids, such as carboxylic acids, for example acetic acid, propionic acid, succinic acid or citric acid, and mineral acids, for example hydrochloric acid, sulfuric acid or phosphoric acid.

[0096] Low polydispersity (Q) and high glass transition temperature (T g The polyarylether copolymer (P) having the above structure is obtained by the process according to the invention. The polyarylether copolymer (P) further has very small amounts of impurities, such as azeotroping agents, such as toluene or chlorobenzene. The content of chloride ions in the product produced according to the invention is also reduced.

[0097] The chloride ion content in the polyarylether copolymer is preferably less than 50 ppm, more preferably less than 30 ppm, and most preferably less than 20 ppm, where the chloride ion content is determined by elemental analysis.

[0098] The present invention therefore also provides a polyarylether copolymer (P) obtainable by the process according to the invention.The polyarylether copolymer (P) generally has a polydispersity (Q) of ≦4, preferably ≦3.5.

[0099] Polydispersity (Q) is the mass average molecular weight (M W ) and number average molecular weight (M n In a preferred embodiment, the polydispersity (Q) of the copolyarylether polymer (P) is in the range of 2.0 to ≦4, preferably in the range of 2.0 to ≦3.5.

[0100] Mass average molecular weight (M W ) and number average molecular weight (M n ) is measured by gel permeation chromatography.

[0101] The polydispersity (Q) and average molecular weight of polyarylether copolymer (P) were measured by gel permeation chromatography (GPC) in dimethylacetamide (DMAc). The mobile phase (eluent) used was DMAc containing 0.5% by weight of lithium bromide. The concentration of polyarylether copolymer (P) (P solution) was 4 mg per ml of solution. After filtration (pore size 0.2 μm), 100 μl of this solution was injected into the GPC system. Four different columns (heated to 80 °C) were used for separation (GRAM precolumn, GRAM 30A, GRAM 1000A, GRAM 1000A; separation material: polyester copolymer, PSS). The GPC system was operated at a flow rate of 1 ml per minute. A DRI-Agilent 1100 was used as the detection system. Molecular weights M in the range of 800-1820000 g / mol were obtained. n A PMMA standard from PSS, having a pH of 10.0 or higher, was used for calibration.

[0102] The polyarylether copolymers (P) obtainable by the process according to the invention generally have a weight average molecular weight (M W The mass average molecular weight (M) is in the range of 10,000 to 150,000 g / mol, preferably in the range of 15,000 to 120,000 g / mol, and particularly preferably in the range of 20,000 to 90,000 g / mol. W ) is measured by gel permeation chromatography (GPC), as described above.

[0103] The polyarylether polymer (P) obtained by the process according to the present invention generally has a glass transition temperature in the range of 100 to 250° C., preferably in the range of 130 to 245° C., particularly preferably in the range of 140 to 230° C. g The measurements of T were carried out on a DSC 2000 (TA Instruments) with a heating rate of 20 K / min. For the measurements, about 5 mg of material was sealed in an aluminum container. In a first heating run, the sample is heated to 290°C, then quenched to -100°C, and then in a second heating run, heated to 290°C at 20 K / min. g The value is determined from the second heating.

[0104] Another subject of the present invention is therefore the polyarylether copolymers (P) obtainable by the process according to the invention.

[0105] Membrane manufacturing The membrane (M) may be produced from the polyarylether copolymer (P) according to the invention by any method known to the person skilled in the art.

[0106] Another subject of the invention is therefore the use of a polyarylether copolymer (P) in a membrane (M).

[0107] Another subject of the invention is therefore a membrane (M) which may be a dense or porous membrane.

[0108] Preferably, the membrane (M) comprising the polyarylether copolymer (P) obtained by the method of the invention has i) providing a solution (S) comprising a polyarylether copolymer (P) and at least one solvent; ii) separating said at least one solvent from the solution (S) to obtain a membrane (M). The present invention is produced by a method comprising the steps of:

[0109] Another subject of the invention is therefore a process for the manufacture of a membrane (M) according to the invention, i) providing a solution (S) comprising a polyarylether copolymer (P) and at least one solvent; ii) separating said at least one solvent from the solution (S) to obtain a membrane (M). The method includes:

[0110] Stage i) In step i), a solution (S) is prepared comprising a polyarylether copolymer (P) and at least one solvent.

[0111] In the context of the present invention, "at least one solvent" means both exactly one solvent and a mixture of two or more solvents.

[0112] The solution (S) may be prepared in step i) by any method known to those skilled in the art. For example, the solution (S) may be prepared in step i) in a conventional vessel, which may include a stirring device and preferably a temperature control device. Preferably, the solution (S) is prepared by dissolving the polyarylether copolymer (P) in at least one solvent.

[0113] Dissolving the polyarylether copolymer (P) in at least one solvent to provide a solution (S) is preferably carried out with stirring.

[0114] Step i) is preferably carried out at elevated temperature, in particular in the range of 20 to 120° C., more preferably in the range of 40 to 100° C. The skilled person will select the temperature according to the at least one solvent.

[0115] The solution (S) preferably comprises the polyarylether copolymer (P) completely dissolved in at least one solvent. This means that the solution (S) preferably does not contain solid particles of the polyarylether copolymer (P). Thus, the polyarylether copolymer (P) preferably cannot be separated from the at least one solvent by filtration.

[0116] The solution (S) preferably comprises 0.001 to 50% by weight of the polyarylether copolymer (P) relative to the total weight of the solution (S), more preferably the solution (S) in step i) comprises 0.1 to 30% by weight of the polyarylether copolymer (P) relative to the total weight of the solution (S), and most preferably the solution (S) comprises 0.5 to 25% by weight of the polyarylether copolymer (P) relative to the total weight of the solution (S).

[0117] The present invention therefore also provides a method for producing a membrane (M), in which the solution (S) in step i) comprises from 0.1 to 30% by weight of polyarylether copolymer (P) relative to the total weight of the solution (S).

[0118] As the at least one solvent, any solvent known to those skilled in the art for polyarylether copolymer (P) is suitable.Preferably, the at least one solvent is water-soluble.Thus, the at least one solvent is preferably selected from the group consisting of N-methylpyrrolidone, dimethylacetamide, dimethylsulfoxide, dimethyllactamide, dimethylformamide and sulfolane.N-methylpyrrolidone and dimethyllactamide are particularly preferred.Dimethyllactamide is most preferred as the at least one solvent.

[0119] Another subject of the invention is therefore also a process for the preparation of a membrane (M), in which at least one solvent is selected from the group consisting of N-methylpyrrolidone, dimethylacetamide, dimethylsulfoxide, dimethylformamide, dimethyllactamide and sulfolane.

[0120] The solution (S) preferably comprises at least one solvent in a range of 50 to 99.999% by weight, more preferably in a range of 70 to 99.9% by weight, and most preferably in a range of 75 to 99.5% by weight, based on the total weight of the solution (S).

[0121] The solution (S) provided in step i) may further comprise additives for producing the membrane.

[0122] Suitable additives for producing membranes are known to those skilled in the art and are, for example, polyvinylpyrrolidone (PVP), polyethylene oxide (PEO), polyethylene oxide-polypropylene oxide copolymer (PEO-PPO) and poly(tetrahydrofuran) (poly-THF). Polyvinylpyrrolidone (PVP) and polyethylene oxide (PEO) are particularly preferred as additives for producing membranes.

[0123] The additive for producing the membrane may be contained in the solution (S) in an amount of, for example, 0.01 to 20 mass %, preferably in the range of 0.1 to 15 mass %, and more preferably in the range of 1 to 10 mass %, relative to the total mass of the solution (S).

[0124] It will be apparent to those skilled in the art that the weight percentages of the polyarylether copolymer (P), at least one solvent, and optionally the additives for producing the membrane contained in the solution (S) typically total 100 weight %.

[0125] The duration of step i) can vary within wide limits. The duration of step i) is preferably in the range from 10 minutes to 48 hours, in particular in the range from 10 minutes to 24 hours and most preferably in the range from 15 minutes to 12 hours. The skilled person will select the duration of step i) so that a homogeneous solution of the polyarylether copolymer (P) in the at least one solvent is obtained.

[0126] For the polyarylether copolymer (P) contained in the solution (S), the embodiments and preferences given for the polyarylether copolymer (P) obtainable in the process according to the invention apply.

[0127] Stage ii) In step ii) at least one solvent is separated from the at least one solution (S) to obtain a membrane (M). After filtering the solution (S) prepared in step i), it is possible to separate at least one solvent from the solution (S) in step ii) to obtain a filtered solution (fS). The following embodiments and preferences for separating at least one solvent from the solution (S) are equally applicable to separating at least one solvent from the filtered solution (fS) used in this embodiment of the present invention.

[0128] Furthermore, a degassing step may be applied to the solution (S) or the filtered solution (fS).

[0129] The separation of the at least one solvent from the solution (S) can be carried out by any method known to the skilled artisan suitable for separating a solvent from a polymer.

[0130] Preferably, the separation of the at least one solvent from the solution (S) is carried out via a phase inversion method.

[0131] Another subject of the invention is therefore also a process for the preparation of a membrane (M), in which the separation of at least one solvent in step ii) is carried out via a phase inversion process.

[0132] When the separation of at least one solvent is performed via a phase inversion process, the resulting membrane (M) is typically a porous membrane.

[0133] A phase inversion process in the context of the present invention means a process in which the dissolved polyarylether copolymer (P) is transformed into a solid phase. The phase inversion process can therefore also be referred to as a precipitation process. According to step ii), the transformation is carried out by separating at least one solvent from the polyarylether copolymer (P). Suitable phase inversion processes are known to those skilled in the art.

[0134] The phase inversion process can be carried out, for example, by cooling the solution (S). During this cooling, the polyarylether copolymer (P) contained in this solution (S) precipitates. Another possibility for carrying out the phase inversion process is to contact the solution (S) with a gaseous fluid that is a non-solvent for the polyarylether copolymer (P). The polyarylether copolymer (P) also precipitates in that case. Suitable gaseous fluids that are non-solvents for the polyarylether polymer (P) are, for example, the protic polar solvents in the gaseous state described below.

[0135] Another phase inversion method which is preferred in the context of the present invention is phase inversion by immersion of the solution (S) in at least one protic polar solvent.

[0136] Thus, in one embodiment of the present invention, in step ii), at least one solvent contained in the solution (S) is separated from the polyarylether copolymer (P) contained in the solution (S) by immersing the solution (S) in at least one protic polar solvent.

[0137] This means that the membrane (M) is formed by immersing the solution (S) in at least one protic polar solvent.

[0138] Suitable at least one protic polar solvent is known to those skilled in the art. The at least one protic polar solvent is preferably a non-solvent for the polyarylether copolymer (P).

[0139] Preferred at least one protic polar solvent is water, methanol, ethanol, n-propanol, isopropanol, glycerol, ethylene glycol and mixtures thereof.

[0140] Step ii) usually involves providing a solution (S) in a form corresponding to the form of the membrane (M) obtained in step ii).

[0141] Thus, in one embodiment of the invention, step ii) comprises casting the solution (S) to obtain a film of the solution (S) or passing the solution (S) through at least one spinneret to obtain at least one hollow fiber of the solution (S).

[0142] Thus, in one preferred embodiment of the present invention, step ii) comprises the following steps: ii-1) casting the solution (S) prepared in step i) to obtain a film of the solution (S); ii-2) from the film of solution (S) obtained in step ii-1), evaporating at least one solvent to obtain a membrane (M) in the form of a film. Includes.

[0143] This means that the membrane (M) is formed by evaporating at least one solvent from a film of the solution (S).

[0144] In step ii-1), the solution (S) can be cast by any method known to those skilled in the art. Usually, the solution (S) is cast using a casting knife heated to a temperature in the range of 20 to 150°C, preferably in the range of 40 to 100°C.

[0145] The solution (S) is typically cast onto a substrate that does not react with the polyarylether copolymer (P) or with at least one solvent contained in the solution (S).

[0146] Suitable substrates are known to those skilled in the art and are for example selected from glass plates and polymeric fabrics, such as non-woven materials.

[0147] To obtain a dense membrane, the separation in step ii) is typically carried out by evaporating at least one solvent contained in the solution (S).

[0148] Another subject of the invention is therefore a membrane (M) which may be a dense or porous membrane.

[0149] Another subject of the invention is therefore a membrane (M) which is asymmetric. EXAMPLES

[0150] The present invention is further illustrated by, but not limited to, the following examples.

[0151] Ingredients used: DCDPS 1: 4,4'-dichlorodiphenyl sulfone, 4,4'-isomer content 99.6% by mass DCDPS 2: 4,4'-dichlorodiphenyl sulfone, 4,4'-isomer content 99.8% by mass DCDPS 3: 4,4'-dichlorodiphenyl sulfone, 4,4'-isomer content 99.95% by mass BP: 4,4'-dihydroxybiphenyl, purity 99.5% by mass Isosorbide: PA isosorbide content >99% by weight, available from Roquette under the trade name POLYSORB® K 2 CO 3 A: Potassium carbonate, anhydrous, average particle size 9.5μm K 2 CO 3B: Potassium carbonate, anhydrous, average particle size 32.6 μm NMP: N-methylpyrrolidone, anhydrous PEO 1 Polyethylene oxide 6000, Mn=5906 g / mol (determined by OH titration) PVP: Polyvinylpyrrolidone; (Luvitec® K40)

[0152] The purity of DCDPS and BP was analyzed by HPLC, while the purity of isosorbide was determined by GC.

[0153] The viscosity number VN of the polyarylether copolymers (P) was determined in 1% by weight solution in NMP according to DIN ISO 1628-1.

[0154] The incorporation rate (percentage of incorporation) of sugar alcohols, such as isosorbide, and further components, such as polyethylene oxide, is 1 H-NMR by CDCl 3 was identified in.

[0155] The resulting polymer suspension was heated to 60° C. and heated under N 2 The mixture is filtered using a heated pressure filter operating at a pressure of 3 bar, using a filter plate with a pore size of 5 μm. The filtration time of each batch is measured.

[0156] The isolation of the polyarylether copolymer (P) is carried out by dropping a solution of the polymer in NMP into demineralized water at room temperature, unless otherwise indicated. The drop height is 0.5 m. The throughput is about 2.5 l per hour. The resulting beads are then extracted with water at 85° C. for 20 hours (water throughput 160 l / h). The beads are then cooled to the glass transition temperature T g It is dried at a lower temperature to a residual moisture content of less than 0.2% by weight.

[0157] The chloride content of the resulting polymer samples was determined by elemental analysis.

[0158] Comparative Example 1: In a 4 L glass reactor equipped with a thermometer, a gas inlet tube and a Dean-Stark trap, 580.063 g (2.02 mol) of DCDPS 1, 211.90 g (1.45 mol) of isosorbide, 102.41 g (0.55 mol) of 4,4'-dihydroxybiphenyl, and 304.052 g (2.20 mol) of potassium carbonate A having a volume average particle size of 9.5 µm were suspended in 1050 ml of NMP under a nitrogen atmosphere.

[0159] The mixture was heated to 190° C. within 1 hour. In the following, reaction times are to be understood as the time during which the reaction mixture was held at 190° C. Water formed in the reaction was continuously removed by distillation.

[0160] After 10 hours of reaction time, the reaction was stopped by adding 1950 ml of NMP and cooled to room temperature (within 1 hour). The potassium chloride formed in the reaction was removed by filtration. The resulting polymer solution was then precipitated in water and the resulting polymer beads were separated and then extracted with hot water (85° C.) for 20 hours. The beads were then dried under reduced pressure (<100 mbar) at 120° C. for 24 hours.

[0161] Example 2: In a 4 liter glass reactor equipped with a thermometer, a gas inlet tube and a Dean-Stark trap, 580.063 g (2.02 mol) of DCDPS 2, 211.90 g (1.45 mol) of isosorbide, 102.41 g (0.55 mol) of 4,4'-dihydroxybiphenyl, and 304.052 g (2.20 mol) of potassium carbonate A having a volume average particle size of 9.5 µm were suspended in 1050 ml of NMP under a nitrogen atmosphere.

[0162] The mixture was heated to 190° C. within 1 hour. In the following, reaction times are to be understood as the time during which the reaction mixture was held at 190° C. Water formed in the reaction was continuously removed by distillation.

[0163] After 10 hours of reaction time, the reaction was stopped by adding 1950 ml of NMP and cooled to room temperature (within 1 hour). The potassium chloride formed in the reaction was removed by filtration. The resulting polymer solution was then precipitated in water and the resulting polymer beads were separated and then extracted with hot water (85° C.) for 20 hours. The beads were then dried under reduced pressure (<100 mbar) at 120° C. for 24 hours.

[0164] Comparative Example 3 In a 4 L glass reactor equipped with a thermometer, a gas inlet tube and a Dean-Stark trap, 580.063 g (2.02 mol) of DCDPS 1, 204.83 g (1.1 mol) of 4,4'-dihydroxybiphenyl, 131.53 g (0.90 mol) of isosorbide, and 304.052 g (2.20 mol) of potassium carbonate A having a volume average particle size of 9.5 µm were suspended in 1050 ml of NMP under a nitrogen atmosphere.

[0165] The mixture was heated to 190° C. within 1 hour. In the following, reaction times are to be understood as the time during which the reaction mixture was held at 190° C. Water formed in the reaction was continuously removed by distillation.

[0166] After 5.5 hours of reaction time, the reaction was stopped by adding 1950 ml of NMP and cooled to room temperature (within 1 hour). The potassium chloride formed in the reaction was removed by filtration. The resulting polymer solution was then precipitated in water and the resulting polymer beads were separated and then extracted with hot water (85°C) for 20 hours. The beads were then dried under reduced pressure (<100 mbar) at 120°C for 24 hours.

[0167] Example 4: In a 4 liter glass reactor equipped with a thermometer, a gas inlet tube and a Dean-Stark trap, 580.063 g (2.02 mol) of DCDPS 2, 204.83 g (1.1 mol) of 4,4'-dihydroxybiphenyl, 131.526 g (0.90 mol) of isosorbide, and 304.052 g (2.20 mol) of potassium carbonate A having a volume average particle size of 9.5 µm were suspended in 1050 ml of NMP under a nitrogen atmosphere.

[0168] The mixture was heated to 190° C. within 1 hour. In the following, reaction times are to be understood as the time during which the reaction mixture was held at 190° C. Water formed in the reaction was continuously removed by distillation.

[0169] After 5 hours of reaction time, the reaction was stopped by adding 1950 ml of NMP and cooled to room temperature (within 1 hour). The potassium chloride formed in the reaction was removed by filtration. The resulting polymer solution was then precipitated in water and the resulting polymer beads were separated and then extracted with hot water (85° C.) for 20 hours. The beads were then dried under reduced pressure (<100 mbar) at 120° C. for 24 hours.

[0170] Example 5: In a 4 liter glass reactor equipped with a thermometer, a gas inlet tube and a Dean-Stark trap, 580.063 g (2.02 mol) of DCDPS 3, 204.83 g (1.10 mol) of 4,4'-dihydroxybiphenyl, 131.53 g (0.9 mol) of isosorbide, and 304.052 g (2.20 mol) of potassium carbonate A having a volume average particle size of 9.5 µm were suspended in 1050 ml of NMP under a nitrogen atmosphere.

[0171] The mixture was heated to 190° C. within 1 hour. In the following, reaction times are to be understood as the time during which the reaction mixture was held at 190° C. Water formed in the reaction was continuously removed by distillation.

[0172] After 5 hours of reaction time, the reaction was stopped by adding 1950 ml of NMP and cooled to room temperature (within 1 hour). The potassium chloride formed in the reaction was removed by filtration. The resulting polymer solution was then precipitated in water and the resulting polymer beads were separated and then extracted with hot water (85° C.) for 20 hours. The beads were then dried under reduced pressure (<100 mbar) at 120° C. for 24 hours.

[0173] Example 6: In a 4 liter glass reactor equipped with a thermometer, a gas inlet tube and a Dean-Stark trap, 580.063 g (2.02 mol) of DCDPS 3, 204.83 g (1.10 mol) of 4,4'-dihydroxybiphenyl, 131.53 g (0.9 mol) of isosorbide, and 304.052 g (2.20 mol) of potassium carbonate B having a volume average particle size of 32.5 µm were suspended in 1050 ml of NMP under a nitrogen atmosphere.

[0174] The mixture was heated to 190° C. within 1 hour. In the following, reaction times are to be understood as the time during which the reaction mixture was held at 190° C. Water formed in the reaction was continuously removed by distillation.

[0175] After 6 hours of reaction time, the reaction was stopped by adding 1950 ml of NMP and cooled to room temperature (within 1 hour). The potassium chloride formed in the reaction was removed by filtration. The resulting polymer solution was then precipitated in water and the resulting polymer beads were separated and then extracted with hot water (85° C.) for 20 hours. The beads were then dried under reduced pressure (<100 mbar) at 120° C. for 24 hours.

[0176] Comparative Example 7: In a 4 liter glass reactor equipped with a thermometer, a gas inlet tube and a Dean-Stark trap, 580.063 g (2.02 mol) of DCDPS 1, 197.383 g (1.06 mol) of 4,4'-dihydroxybiphenyl, 131.526 g (0.90 mol) of isosorbide, 236.24 g (0.04 mol) of PEO 1, and 345.52 g (2.50 mol) of potassium carbonate A having a volume average particle size of 9.5 μm were suspended in 1050 ml of NMP under a nitrogen atmosphere.

[0177] The mixture was heated to 190° C. within 1 hour. In the following, reaction times are to be understood as the time during which the reaction mixture was held at 190° C. Water formed in the reaction was continuously removed by distillation.

[0178] After 5 hours of reaction time, the reaction was stopped by adding 1950 ml of NMP and cooled to room temperature (within 1 hour). The potassium chloride formed in the reaction was removed by filtration. The resulting polymer solution was then precipitated in water and the resulting polymer beads were separated and then extracted with hot water (85° C.) for 20 hours. The beads were then dried under reduced pressure (<100 mbar) at 120° C. for 24 hours.

[0179] Example 8: In a 4 liter glass reactor equipped with a thermometer, a gas inlet tube and a Dean-Stark trap, 580.063 g (2.02 mol) of DCDPS 3, 197.383 g (1.06 mol) of 4,4'-dihydroxybiphenyl, 131.526 g (0.90 mol) of isosorbide, 236.24 g (0.04 mol) of PEO 1, and 345.52 g (2.50 mol) of potassium carbonate A having a volume average particle size of 9.5 μm were suspended in 1050 ml of NMP under a nitrogen atmosphere.

[0180] The mixture was heated to 190° C. within 1 hour. In the following, reaction times are to be understood as the time during which the reaction mixture was held at 190° C. Water formed in the reaction was continuously removed by distillation.

[0181] After 4.5 hours of reaction time, the reaction was stopped by adding 1950 ml of NMP and cooled to room temperature (within 1 hour). The potassium chloride formed in the reaction was removed by filtration. The resulting polymer solution was then precipitated in water and the resulting polymer beads were separated and then extracted with hot water (85°C) for 20 hours. The beads were then dried under reduced pressure (<100 mbar) at 120°C for 24 hours.

[0182] The viscosity numbers and filtration times are shown in Table 1 below.

[0183] [Table 1]

[0184] The polyarylether copolymers (P) obtained by the process of the present invention exhibit high molecular weight, as indicated by the viscosity number, and low chloride content.

[0185] The membrane was prepared as follows: In a three-neck flask equipped with a magnetic stirrer, 78 ml of methylpyrrolidone (NMP), 5 g of polyvinylpyrrolidone (PVP, Luvitec® K40), and 17 g of polyarylether copolymer (P) are added.

[0186] The mixture is heated at 60° C. with gentle stirring until a homogeneous, clear, viscous solution is obtained. The solution is degassed overnight at room temperature. The membrane solution is reheated at 60° C. for 2 hours and then cast onto a glass plate at 60° C. using a casting knife (300 microns) using an Erichsen coater operating at a speed of 5 mm / min. The membrane film is allowed to rest for 30 seconds and then immersed in a water bath at 25° C. for 10 minutes.

[0187] After removing the membrane from the glass plate, the membrane is carefully transferred into a water bath for 12 hours. The membrane is then transferred to a bath containing 2500 ppm NaOCl at 50° C. for 4.5 hours to remove the PVP. After that process, the membrane is washed with water at 60° C. and once with a 0.5% by weight sodium bisulfite solution to remove the active chlorine. After several washing steps with water, the membrane was stored in a wet state until the evaluation began.

[0188] In most cases, a continuous film of flat sheets is obtained with dimensions of at least 10 x 15 cm in size, which have the fine structural characteristics of an ultrafiltration (UF) membrane, exhibiting a thin upper skin layer (1-3 microns) and an underlying porous layer (thickness: 100-150 microns).

[0189] The polyarylether copolymers (P) obtained in Comparative Example C3, Examples 4 and 5, Comparative Example C7, and Example 8 were used to prepare membranes.

[0190] [Table 2]

[0191] PWP: Pure water permeability MWCO: Molecular Weight Cutoff The turbidity of the solutions prepared for the membrane formulations was measured using a Hach TL2360 turbidity meter operating at a wavelength of 860±30 nm.

[0192] Membrane Rating: The pure water permeability of the membrane was tested using ultrapure water (salt-free water, filtered by Millipore UF system) using a pressure cell with a diameter of 60 mm. In subsequent tests, solutions of different PEG standards were filtered at a pressure of 0.15 bar. The molecular weight cut-off was determined by GPC measurements of the feed and permeate.

[0193] The turbidity of the dope solution of the polyarylether copolymer (P) according to the invention is surprisingly lower compared to the solutions prepared from the comparative examples.

[0194] The elongation at break was measured in a tensile test according to ISO 527. The membranes were stored in water and tensile specimens were punched out of the membrane sheets. The wet specimens were immediately clamped in the tensile machine and tested. Typically, five specimens were tested for each membrane.

[0195] Membranes produced with the polyarylether polymer (P) according to the invention exhibit high permeability, good molecular weight cut-off and improved tensile elongation.

Claims

1. A process for the preparation of a polyarylether copolymer (P), comprising the steps of: As an ingredient, (A1) at least one dihalodiphenyl sulfone component having a 4,4'-dihalodiphenyl sulfone content of at least 99.65% by weight, based on the total weight of the at least one dihalodiphenyl sulfone component in component (A1); (B1) at least one sugar alcohol selected from the group consisting of isosorbide, isomannide and isoidide; (B2) at least one aromatic dihydroxyl component; (B3) optionally at least one dihydroxyl polyalkylene oxide; A reaction mixture (R G ) The reaction mixture (R G ) is the reaction mixture (R G 35 to 70 mol % of component (B1), 30 to 65 mol % of component (B2), and optionally 0.0 to 5 mol % of component (B3) based on the total amount of components (B1), (B2), and optionally (B3) contained in The method.

2. The reaction mixture (R G ) is the reaction mixture (R G 2. The method according to claim 1, wherein the composition comprises 35 to 69 mol % of component (B1), 31 to 65 mol % of component (B2), and optionally 0.0 to 4 mol % of component (B3), based on the total amount of components (B1), (B2), and optionally (B3) contained in the copolymer.

3. The reaction mixture (R G ) is the reaction mixture (R G 3. The method according to claim 1, wherein the composition comprises 37 to 67 mol % of component (B1), 33 to 63 mol % of component (B2), and optionally 0.0 to 3 mol % of component (B3), based on the total amount of components (B1), (B2), and optionally (B3) contained in the copolymer.

4. The reaction mixture (R G ) is further (C) at least one aprotic polar solvent, and (D) at least one carbonate component. The method according to any one of claims 1 to 3, comprising:

5. The dihydroxyl component (B2) is G 5. The process according to claim 1, wherein the component (B2) is at least 50% by weight of 4,4'-dihydroxybiphenyl, based on the total weight of the component (B2) contained in the copolymer (B1).

6. Component (A1) is dichlorodiphenyl sulfone having a content of 4,4′-dichlorodiphenyl sulfone of at least 99.65% by weight, based on the total weight of dichlorodiphenyl sulfone in component (A1), and Difluorodiphenyl sulfone having a 4,4'-difluorodiphenyl sulfone content of at least 99.65% by weight based on the total weight of difluorodiphenyl sulfone in component (A1). The method according to any one of claims 1 to 5, wherein the compound is selected from the group consisting of:

7. 7. The method of any one of claims 1 to 6, wherein component (C) is at least one solvent selected from the group consisting of anisole, dimethylformamide, dimethylsulfoxide, sulfolane, N,N-dimethylacetamide, N-methyl-2-pyrrolidone, and N-ethyl-2-pyrrolidone.

8. A polyarylether copolymer (P) obtainable by the process according to any one of claims 1 to 7.

9. 9. Use of the polyarylether copolymer (P) according to claim 8 in a membrane (M).

10. A membrane (M) comprising a polyarylether copolymer (P) according to claim 8.

11. The membrane (M) according to claim 10, wherein the membrane (M) is a dense membrane or a porous membrane.

12. 12. The membrane according to claim 10 or 11, wherein the membrane (M) is asymmetric.

13. A method for producing a membrane (M) according to any one of claims 10 to 12, comprising the steps of: i) providing a solution (S) comprising said polyarylether copolymer (P) and at least one solvent; ii) separating said at least one solvent from the solution (S) to obtain a membrane (M); The method comprising:

14. 14. The method of claim 13, wherein the at least one solvent is selected from the group consisting of N-methylpyrrolidone, N-dimethylacetamide, dimethylsulfoxide, dimethylformamide, dimethyllactamide, and sulfolane.

15. 15. The method according to claim 13 or 14, wherein the solution (S) provided in step i) comprises a polyarylether polymer (P) in the range of 0.1 to 30% by weight relative to the total weight of said solution (S).

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